Opc data Access Automation Specification

A Sample OPC Automation Error Code Fragment 

81 

 

---

OPC Data Access Automation Specification2.02 

Dim AnOpcServer As OPCServer 

 

Private Sub Command1_Click() 

On Error GoTo testerror 

Set AnOpcServer = New OPCServer 

‘ assuming fuzz does’nt exist so the connect fails and your 

‘VB code goes to the label testerror 

AnOpcServer.Connect ("fuzz")  

 

Time = AnOpcServer.CurrentTime 

Debug.Print Time 

 

testerror: 

Debug.Print Err.Number 

End Sub

 

82 

 

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OPC Data Access Automation Specification2.02 

7

 

Appendix B – Sample String Filter Syntax Function 

Syntax

 

BOOL MatchPattern(  LPCTSTR 

string

, LPCTSTR 

pattern

, BOOL 

bCaseSensitive

 )

 

Return Value

 

If 

string

 matches 

pattern

, return is 

TRUE

; if there is no match, return is 

FALSE

. If either 

string

 or 

pattern

 is Null, return is 

FALSE;

 

Parameters 

string

    String to be compared with pattern. 

pattern

   Any string conforming to the pattern-matching conventions described in Remarks. 

bCaseSensitive

  

TRUE

 if comparison should be case sensitive. 

Remarks

 

A versatile tool used to compare two strings. The pattern-matching features allow you to use wildcard characters, character 

lists, or character ranges, in any combination, to match strings. The following table shows the characters allowed in 

pattern

 

and what they match: